Generally, LCD devices are apparatus for displaying images by controlling aligned status of liquid crystal having a dielectric anisotropy by using an electric field generated by a potential difference between electrodes facing to each other, and then adjusting transmittance of light according to the aligned status of the liquid crystal.
The LCD device is generally equipped with a liquid crystal display panel and a backlight unit disposed at a rear side of the liquid crystal display panel. And, light generated from the backlight unit is made to be incident on the liquid crystal display panel, so that images are displayed on a front surface of the liquid crystal display panel. Accordingly, the related liquid crystal display panel is configured to display images only on the front surface thereof.
However, recently, as LCD devices has been widely used, a dual liquid crystal display device that can implement images on both the front and the rear surfaces of the liquid crystal display device using one liquid crystal display panel is proposed so as to view the liquid crystal display device at various angles
The dual liquid crystal device 1, as shown in FIGS. 1a and 1b, includes a liquid crystal display panel 2, a front polarizer 3 attached at a front surface portion of the liquid crystal display panel 2, a rear polarizer 4 attached at a rear surface portion of the liquid crystal display panel 2, a front backlight unit 7 disposed at the front surface portion of the liquid crystal panel 2, and a rear backlight unit 8 disposed at the rear surface portion of the liquid crystal panel 2. And, the dual liquid crystal device 1 further includes a front micro reflective film 5 interposed between the front polarizer 3 and the front backlight unit 7, and a rear micro reflective film 6 interposed between the rear polarizer 4 and the rear backlight unit 8.
Here, the liquid crystal display panel 2 includes a thin film transistor substrate 2a provided with thin film transistors (not shown) thereon, a color filter substrate 2b facing the thin film transistor substrate 2a and provided with a color filter layer (not shown), and a liquid crystal layer 2c interposed between both substrates 2a and 2b. 
The front polarizer 3 and the rear polarizer 4 transmit light vibrating only in one direction so as to polarize natural light, and each polarizing axis thereof is disposed in a direction perpendicular to each other.
The front micro reflective film 5, when the light generated from the front backlight unit 7 transmits the liquid crystal display panel 2 and then images are implemented on the rear surface thereof, serves to reflect external light irradiated to the rear surface. The rear micro reflective film 6, when the light generated from the rear backlight unit 8 transmits the liquid crystal display panel 2 and then images are implemented at the front side thereof, serves to reflect the external light irradiated to the front side. Accordingly, a problem that it is difficult to view a screen of the LCD device 1 where the bright external light is introduced thereinto can be solved. That is, when the light from the front or rear backlight unit 7, 8 is less bright than the external light, the images on the liquid crystal display device 1 may not be viewed. Here, reflecting the external light by using the front micro reflective film 5 and the rear micro reflective film 6, light efficiency can be enhanced, thereby rendering the liquid crystal display device 1 capable of viewing the images clearly.
The front backlight unit 7 and the rear backlight unit 8 include optical guide plates 7a, 8a, light sources 7b, 8b disposed at each one lateral surface of the optical guide plates 7a, 8a, and light source reflectors 7c, 8c encompassing some of circumferences of the light sources 7b, 8b, respectively.
Meanwhile, though it is not shown, a compensation plate for compensating a phase of light, a diffusion film for diffusing the light, etc. may be further included.
With such a configuration, when the front backlight unit 7 is turned on, as shown in FIG. 1a, the images are implemented on the rear surface. When the rear backlight unit 8 is turned on, as shown in FIG. 1b, the images are implemented on the front surface.
However, such a dual LCD device 1 has problems in that the images cannot be simultaneously displayed on the front and rear surfaces, but can selectively displayed on the front or rear surface. Additionally, images cannot be simultaneously displayed on the front surface and the rear surface differently from each other.